Harlequin ichthyosis describes a severe erythrodermic ichthyosis that causes a distinctive and alarming appearance at birth. It is a very rare autosomal recessive disorder with only around 200 cases reported in the literature.

A male neonate was born prematurely to para two mother on 34 weeks of gestation by normal vaginal delivery. His Appearance, Pulse, Grimace, Activity, Respiration (APGAR) score was 6-8.

There was a history of consanguinity. Mother's obstetric history was significant with one abortion and one preterm birth with the baby having similar disorder.

On physical examination, birth weight of the baby was 1,700 g. The baby was covered with severely thickened, waxy, yellowish skin that was irregularly split to reveal erythematous fissures. Severe ectropion and eclabium was present and the ears were hypoplastic and nose was flattened. His hands and feet were covered with circumferential bands [Figure 1] and [Figure 2].

The baby was shifted to the intensive care unit and was managed conservatively. The baby was nursed in a humidified incubator. Umbilical cannulation was set up to establish venous access. Appropriate fluids and antibiotics were administered. Emollients were applied and ectropion was covered with eye pads after applying antibiotic ointment locally.

Dermatologist's opinion was sought and the disease was provisionally diagnosed as harlequin ichthyosis.

The baby died of respiratory failure 2 days after birth.

The earliest description of harlequin ichthyosis was by Oliver Hart, a Charleston pastor, in 1750. [1],[2]

It is a fatal disease in which neonates die within a few days secondary to respiratory insufficiency or sepsis. [3]

The causative mutation is in ABCA12 that plays a critical role in the formation of lamellar granules. Mutation causes different lipid transport that significantly impacted normal development of skin barrier. [4]

Affected neonates are encased in a hard armour-like, thickened stratum corneum that results in severe immobilization and restricts ventilation. Other features are severe ectropion, eclabium, rudimentary ears, flattened nose, and edematous hands and feet with circumferential bands. These babies are at serious risk of hypothemia, dehydration, respiratory difficulty, and electrolyte abnormalities.

Improved neonatal care and early retinoid therapy have led to prolonged survival of these babies, but the survivors are at a risk of severe erythrodermic ichthyosis. [5] The early administration of systemic retinoids, in particular acitretin with an initial dose of 1 mg/kg/day has been shown to result in shedding of the large keratotic plates as well as improvement of ectropion and eclabium.

The diagnosis is based on characteristic clinical features, skin biopsy, and ABCA12 gene mapping.

Identifying premature keratinization at 20 weeks plus gestation or ultrastructural abnormalities at 18 weeks in fetal skin biopsy aids in diagnosis. The fetal foot length that is shorter than femur length may be an important and probably the first marker seen in the second trimester during the ultrasonographical prenatal diagnosis. With the discovery of mutations in the ABCA12 gene as the molecular basis of harlequin ichthyosis, however, most cases can now be considered for much earlier DNA-based prenatal diagnosis.

The parents of all the diagnosed patients must receive genetic counseling concerning the potential risk of affected offspring and prenatal diagnosis.